#
# This source file is part of the EdgeDB open source project.
#
# Copyright 2020-present MagicStack Inc. and the EdgeDB authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#


from __future__ import annotations
from typing import *

from collections import deque

from edb.edgeql import tokenizer
from edb._edgeql_rust import Token


class EdgeQLLexer(object):
    inputstr: str
    tokens: Optional[Deque[Token]]
    filename: Optional[str]
    end_of_input: Tuple[int, int, int]

    def __init__(self):
        self.filename = None  # TODO

    def setinputstr(
        self,
        source: Union[str, tokenizer.Source],
        filename: Optional[str]=None,
    ) -> None:
        if isinstance(source, str):
            source = tokenizer.Source.from_string(source)

        self.inputstr = source.text()
        self.filename = filename
        self.tokens = deque(source.tokens())
        self.end_of_input = self.tokens[-1].end()

    def token(self) -> Token:
        if self.tokens:
            return self.tokens.popleft()
